GM V8 Diesels

The second energy crisis that came with the Iranian revolution forced Detroit to improve its corporate fuel economy on their large vehicles. The diesel was seen as a way of having one’s cake and eating it, too — good fuel economy without sacrificing the size and cushy ride that American luxury car buyers expected.

As a result around 1978 - 88 GM/Detroit/Oldsmobile produced a 5.7L V8 diesel.... with 120 HP later ones with 105 HP ...

Basically a trainwreck of an engine, woefully under-engineered and fraught with issues even in the automobile world...and re-builds were very common... almost expected, ..... the engine nearly ruined Oldsmobile's reputation... If this is installed in a boat, marinised by some un-known outfit (never marinised by GM/Detroit), I would RUN and never look back!

Suggest that the owner may wish to re-consider his stance of it being a GM 5.7L diesel... :)

The 6.2 and 6.5 L V8 engines are very different engines indeed
 
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The second energy crisis that came with the Iranian revolution forced Detroit to improve its corporate fuel economy on their large vehicles. The diesel was seen as a way of having one’s cake and eating it, too — good fuel economy without sacrificing the size and cushy ride that American luxury car buyers expected.

As a result around 1978 - 88 GM/Detroit/Oldsmobile produced a 5.7L V8 diesel.... with 120 HP later ones with 105 HP ...

Basically a trainwreck of an engine, woefully under-engineered and fraught with issues even in the automobile world...and re-builds were very common... almost expected, ..... the engine nearly ruined Oldsmobile's reputation... If this is installed in a boat, marinised by some un-known outfit (never marinised by GM/Detroit), I would RUN and never look back!

Suggest that the owner may wish to re-consider his stance of it being a GM 5.7L diesel... :)

The 6.2 and 6.5 L V8 engines are very different engines indeed

Oh ok so he may be right, how would I tell if its a 5.7 or a 6.2-6.5?
 
I had a GM 6.2 V8 diseasel in my Stonefield 6x4 truck, cooling was it's biggest problem, great power and torque and could rev quite high for a naturally aspirated diesel, I replaced the 3lt V6 Ford engine that was original fitment in the truck, I was always looking for ways to improve the cooling as with the biggest radiator we could squeeze in the engine bay we were still limited to about half speed if on a long run, for a quick dash it could fly, but after about 2 minutes it would start to over heat.
The lad I had to drive and operate it managed to seize the engine on his way home for the weekend.

For a big diesel it is quite light being an aluminium block with cast iron liners, but still way heavier than the V6 it replaced, other problems were the lack of a decent vacuum pump for the brakes, fuel consumption was quite good at 28mpg @ 50mph. and way better than the 7mpg of the V6 Ford or the 3mpg of the 4,2V8.
5.2tonnes of brick shaped truck powered by the 6.2GM engine:
Stonefield6x4b.jpg

We had three Stonefields, the one 6x4 above, two 4x4, one powered by the 3lt V6 Ford and the other with a 4.2 Chrysler V8 petrol.
 
Re: Ather Marine


Thats what i thought but the owner wont have it!!!
i was told turbo was 6.2 and non turbo 6.5 i think i'd prefer a non turbo as less to go wrong!!
6.5 could be turbo or N/A not seen a 6.2 turbo and the dealer we got to put the 6.2 in the Stonefield only had the 6.2 natural aspirated or 6.5turbo all his engines were ex Army Hummer engines.
 
Hi Syd

I don't know who else marinises these engines other than Samurai - who let a good opportunity slip through their hands..

The basic GM block is fine and very robust - especially the non-turbo version. Maybe get hold of one and rebuild it yourself?

At one time this was the favourite conversion for the Bayliner 2855 and 2855 wide-body. I nearly bought one once but ended up with my Windy.
Wow that is a blast from the past, did not they go bust? Last time I was in Weston the Samurai garage had gone.
Samurai were the ones that put the 6.2 in my Stonefield truck in 1996.
 
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